The following description is provided to assist the understanding of the reader. None of the information provided or references cited is admitted to be prior art.
The production of steel in an electric arc furnace (EAF) typically results in a byproduct of about 15-20 kilograms of toxic heavy-metal dust per ton of produced steel. EAF dust has been classified as a hazardous waste by the Environmental Protection Agency and is the largest volume hazardous waste produced in the United States. In 2007, approximately one million tons of EAF dust was produced in the United States by American steel electric arc furnaces.
Various EAF dust recycling methods have been developed, resulting in the development of a new industry directed to EAF dust recycling. More than 750,000 tons of EAF dust are currently recycled in the United States each year. Various recycling processes such as the Waelz Kiln process are used to recover zinc, stainless steel additives, and iron-rich slag waste from the EAF dust. However, traditional EAF dust recycling processes require large amounts of EAF dust, and thus it is generally not cost effective to implement such processes on-site with typically-sized arc furnaces. As such, steel production companies generally must ship their EAF dust off-site for recycling and/or disposal at additional cost.